摘要
为了研究Banach空间中单位等边三角形的高与空间几何性质之间的关系,利用几何方法,引入了新的几何常数h(X).给出了h(X)的下界,证明了一个Banach空间X是一致非方的当且仅当h(X)>1/2,并由此说明当h(X)>1/2时空间X对非扩张映射有不动点性质.
In order to study the relation between heights of unit equilateral triangles and geometric properties of the underlying space,a new geometric constant h（X） is introduced via geometric method.The lower bound of h（X）is presented.It is proved that a Banach space X is uniformly nonsquare if and only if the inequality h（X）1/2 holds,and that a Banach space X has the fixed point property for nonexpansive mappings whenever the inequality h（X）1/2 holds.
出处
《哈尔滨理工大学学报》
CAS
北大核心
2011年第1期107-109,共3页
Journal of Harbin University of Science and Technology
基金
黑龙江省教育厅科学技术研究项目(11541069)
关键词
不动点性质
非扩张映射
非方常数
一致非方空间
fixed point property
nonexpansive mapping
nonsquare constants
uniformly nonsquare space
